RBP4 and type 2 diabetes mellitus: Retinol and its derivates have been linked to the regulation of pancreatic β-cell mass, β-cell function, and lipid metabolism, which are involved in the pathogenesis of CVD and T2D.2,3 RBP4 has been described to promote atherosclerosis through macrophage foam cell formation and induction of oxidative vascular damage by mitochondrial dysfunction,4,5 which in turn increases the risk of ischemic CVD.